title: Compatibility and stability of morphine sulphate and naloxone hydrochloride in 0.9% sodium chloride for injection.
abstract: BACKGROUND
  Naloxone may be administered in conjunction with morphine to reduce the risk of opioid-induced pruritis. Combining these drugs for coadministration may be beneficial, but little is known about their physical compatibility and stability in combined solutions.
  
  
  OBJECTIVE
  To describe the physical compatibility and stability of morphine sulphate and naloxone hydrochloride (at various concentrations) in IV admixtures.
  
  
  METHODS
  The physical compatibility and stability of admixtures of morphine 1000 μg/mL and naloxone 4 μg/mL, 12.5 μg/mL, and 25 μg/mL in 0.9% sodium chloride were studied. For each concentration of naloxone, one bag was stored at room temperature (22°C) for 72 h and one bag was stored under refrigeration (4°C) for 30 days. For all preparations, physical characteristics, including pH, colour, and formation of precipitate, were evaluated. The samples were also analyzed by a stability-indicating high-performance liquid chromatographic method. Stability was defined as the retention of at least 90% of the initial concentration.
  
  
  RESULTS
  No notable changes in pH or colour and no macroprecipitation were observed in any of the preparations after storage at 22°C for up to 72 h or at 4°C for up to 30 days. All preparations maintained more than 90% of the initial concentrations of morphine and naloxone at the end of the respective study periods. The calculated lower limit of the 95% confidence interval also indicated that 90% or more of the initial concentration remained at the end of each study period.
  
  
  CONCLUSIONS
  Admixtures of morphine sulphate and naloxone hydrochloride were stable for 72 h at room temperature and for 30 days with refrigeration.
authors.affiliation: , BSc(Pharm), was, at the time of this study, a Hospital Pharmacy Practice Resident with the Department of Pharmacy, Children's and Women's Health Centre of British Columbia, Vancouver, British Columbia. She is now a Pharmacist with the Department of Pharmacy, Kelowna General Hospital, Kelowna, British Columbia.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Kistner
authors.forename: Mary H H
authors.initials: MH
authors.lastname: Ensom
authors.forename: Diane
authors.initials: D
authors.lastname: Decarie
authors.forename: Gillian
authors.initials: G
authors.lastname: Lauder
authors.forename: Roxane R
authors.initials: RR
authors.lastname: Carr
keywords: compatibility; morphine; naloxone